Method of making a buffing element



06L 965 s. R. CHURCHILL 3,212,868

I METHOD OF MAKING A BUFFING ELEMENT I Original Filed Feb. 2, 1959 8 Sheet s-Sheet 1 IN V EN TOR.

ATTOIENEY Oct. 19, 1965 G. R. CHURCHILL 3,212,868

METHOD OF MAKING A BUFF ING ELEMENT Original Filed Feb. 2, 1959 8 Sheets-Sheet 2 INYENTOR. 6601 E C'burcfi/W BY M MM ATTORNEY Oct. 19, 1965 G. R. CHURCHILL METHOD OF MAKING A BUFFING ELEMENT 8 Sheets-Sheet 3 Original Filed'Feb. 2. 1959 IN VEN TOR.

AT TORNE Y Oct. 19, 1965 G. R. CHURCHILL 3,212,868

METHOD OF MAKING A BUFFING ELEMENT Original Filed Feb. 2, 1959 8 Sheets-Sheet 4 IN VEN TOR.

fuhe MM 4 TTORNEV Oct. 19, 1965 G. R. CHURCHILL METHOD OF MAKING A BUFFING ELEMENT 8 Sheets-Sheet 5 Original Filed Feb: 2, 1959 INVENTOR. (bx/rah A T Top/v5 v Edi 8 Sheets-Sheet 6 G- R. CHURCHILL METHOD OF MAKING A BUFFING ELEMENT R NJ miltlm-iiiiilltl 1-1!! :iiwwi -liil- -1 N k A I am AAAAA/ 4/ x 444) n 442 443 I. llll Ill llllllllul'll I'll-1| I l l I i 1 I I I l|l 9w V VV/VI Y/V VV Oct. 19, 1965 Original Filed Feb. 2, 1959 IN V EN TOR. E. C'fiz/mfiM/ EW- ATTORNEY Oct. 19, 1965 G. R. CHURCHILL METHOD OF MAKING A BUFFING ELEMENT 8 Sheets-Sheet 7 Original Filed Feb. 2, 1959 Z m 2 HWHHHMMWN mm INVENTOR. Gew de E: Cburz'fifl/ BY ATTORNEY Oct. 19, 1965 G. R. CHURCHILL 3,212,868

METHOD OF MAKING A BUFFING ELEMENT Original Filed Feb. 2, 1959 l 8 Sheets-Sheet 8 FIG.24 /e4 INVENTOR. Genr E. CbUm/ MW. 61mm A T TOQNE Y United States Patent 3,212,868 METHOD OF MAKING A BUFFING ELEMENT George R. Churchill, Cohasset, Mass., assiguor to George R. Churchill Company, Inc., Hingham, Mass., a corporation of Massachusetts Original application Feb. 2, 1959, Ser. No. 790,560, new Patent No. 3,080,689, dated Mar. 12, 1963. Divided and this application Jan. 13, 1961, Ser. No. 82,631

16 Claims. (Cl. 51293) This application is a division of my copending application, Serial No. 790,560, for Bufiing Wheel and Method of Making the Same, filed February 2, 1959, now Patent No. 3,080,689, issued March 12, 1963.

This invention relates to a method and apparatus for making a buffing element.

The invention has for an object to provide a novel and improved method of producing a corrugated bufiing element for the purpose defined in a simple and economical manner.

A further object of the invention is to provide novel and improved apparatus for producing a bufiing element of the type specified in a rapid, efiicient and economical manner.

With these general objects in view and such others as may hereinafter appear, the invention consists in the method of and apparatus for making a buffing element as hereinafter described and particularly defined in the claims at the end of this specification.

In the drawing-s illustrating the preferred embodiment of the invention:

FIG. 1 is a side elevation of a buffing element comprising a multi-ply cloth strip of corrugated buifing material produced in accordance with the present invention;

FIG. 2 is a plan view of the same;

FIG. 3 is a vertical cross section taken on the line 33 of FIG. 1;

FIG. 4 is a horizontal section taken on the line 44 of FIG. 1;

FIG. 5 is a side elevation partly broken away of a buffing wheel section embodying the corrugated bufiing material shown in FIG. 1;

FIG. 6 is an end view of the same partly in vertical cross section;

FIG. 7 is a side elevation of a spirally wound buffing roll embodying an elongated strip of the corrugated bufiing material shown in FIG. 1;

FIG. 8 is a plan view of a portion of the apparatus for producing the present bufiing element;

FIG. 9 is a vertical section taken on the line 9-9 of FIG. 8 showing a multi-ply cloth web stitched along a central line;

FIG. 10 is a vertical section on the line 10-10 of FIG. 8 showing the cloth Web folded upon itself;

FIG. 11 is a plan view of another portion of the apparatus for producing the corrugated buffing element and comprises a continuation of the view shown in FIG. 8;

FIG. 12 is a front elevation at a larger scale of a portion of the apparatus shown in FIG. 11;

FIG. 13 is a vertical section taken on the line 13-13 of FIG. 12;

FIGS. 14, and 16 are vertical cross sections taken on the lines 1414, 1515 and 16-16, respectively, of FIG. 11;

FIG. 17 is an end view of a modified form of multi-ply cloth web from which the present corrugated element may be produced;

FIG. 18 is an end view showing the web of FIG. 17 folded upon itself;

FIG. 19 is an end view of an unfolded multi-ply web which may be employed in producing the present corrugated bufling element;

FIG. 20 is a perspective view partly in cross section of another modified form of a corrugated buffing element produced in accordance with the present invention;

FIG. 21 is a perspective view illustrating partly in cross section still another form of corrugated material produced in accordance with the present invention;

FIG. 21a is a perspective view illustrating partly in cross section a still further form of corrugated material produced in accordance with the present invention;

FIG. 22 is a plan view illustrating the present corrugated strip being helically wound and clamped upon a tubular core to produce a bufiing roll;

FIG. 23 is a detail view in vertical cross section taken on the line 23-23 of FIG. 22;

FIG. 24 is a plan view illustrating the present corrugated strip being stapled to a helical metal band from which a bufling wheel section or roll may be produced;

'FIG. 25 is a detail view in vertical cross section taken on the line 2525 of FIG. 24; and

FIGS. 26 and 27 are similar views illustrating modified forms of the stapled buffing element shown in FIG. 25.

In general the present invention contemplates a novel and improved method and apparatus for making a bufling element for use in maknig a buffing wheel or bufiing roll.

The illustrated bufiing element produced in accordance with the present novel method and apparatus comprises an elongated strip of bufiing material provided with transversely extended, substantially uniform corrugations closely compacted together. In practice an elongated multi-ply web of buffing material, such as cloth or other known surface treating material is folded transversely upon itself along a longitudinal center line to provide a U-shaped strip. The folded strip is then advanced through corrugating apparatus, and uniform, closely compacted corrugations are formed in the strip. In order to facilitate control and guide the strip to and through the corrugating apparatus an elongated wire is preferably extended within the folded edge of the strip. Provision is made for retaining the corrugations in their compacted condition.

In one embodiment of the invention the corrugated structure may be retained in it closely compacted or contracted condition by stitching passing through the cloth in a direction perpendicular to the direction of the corrugations. In another embodiment of the invention the corrugated strip may be stapled to a metal band so that.

the staples serve to retain the corrugations in their compacted condition. In still another embodiment of the invention the elongated strip of corrugated butting material may be helically wound upon a tubular core member and clamped thereto to retain the corrugations in their.

prise a single or multi-ply or laminated web of cloth orother buffing material 12 folded medially upon itself about a Wire 14 and provided with substantially uniform,

longitudinally contracted or compressed corrugations 16, as shown in FIG. 2. In the embodiment of the invention shown in FIG. 1 the corrugations 16 extend uniformly transversely of the strip from a point immediately above the wire 14 extended within the folded edge '18 of the strip to the outer or opposite edge 20 of the strip, the material below the Wire along the folded edge being closely gathered or puckered together as indicated at 22. The corrugations may be maintained in their closely compacted condition by stitching 24 passing through the corrugations, as shown in FIG. 4, along a line above the Wire 14.

The corrugated strip of bufiing material 10 thus prepared may be cut to length and formed into a ring 26, as shown in FIGS. 5 and 6, which may be secured to a metal 3 disk 28 by staples 30, the disk 28 being provided with a central flanged opening 32 for mounting the ring or single section bufiing wheel on an arbor together with similar sections which may be clamped together to produce a relatively wide bufling wheel. FIG. 7 illustrates another form of buffing wheel or roll 34 which may be produced with the present bufling element wherein an elongated strip of corrugated buffing material may be helically wound upon a tubular core member 36 between the convolutions of a springlike metal member 38, and thereafter the spring may be compressed to grip and retain the corrugated material therebetween.

Referring now to FIGS. 8 to 16 illustrating the method of and apparatus for producing the buffing element shown in FIG. 1, a multi-ply web of cloth 12, preferably secured together medially and longitudinally thereof by stitching 40, may be withdrawn from a supply roll 42 thereof and passed between folding plates 44, 45 to fold the web transversely upon itself providing a strip U- shaped in cross section, the folded strip being advanced into a supporting guide 46 having an upstanding rear edge 48 and an overlying curved portion 50 as shown in FIG. 10.

As illustrated in FIG. 11, which comprises a continuation of FIG. 8, provision is made for applying the wire 14 within the folded strip 10 as the latter is advanced through the supporting guide 46. As herein shown, the wire may be withdrawn from a supply roll 52 and passed through a wire straightening device indicated generally at 54 and around a guide wheel 56 which extends between the sides of the folded strip to dispose and align the wire within the folded edge, as shown in cross section in FIG. 14. The wire 14 is arranged to pass through a small diameter stationary guide tube 58 prior to passing into the corrugating mechanism, indicated generally at 60, the folded strip being advanced over the stationary tube during the corrugating operation. As illustrated in FIG. 15, the tube 58 may be supported by a plate 62 extended between the folded strip and attached to a frame member 64. In operation the guide tube 58 retains the folded edge of the strip firmly against a backing plate 66 during the corrugating operation.

The continuously advancing folded strip then passes between upper and lower .driven corrugating gears 68, 70 illustrated in detail in FIGS. 12 and 13 and which cooperate to shape the multi-ply material as it passes therebetween to provide uniform transverse open corrugations therein from a point spaced a short distance from the guide tube 58 over which the folded edge is wrapped to the opposite marginal edge of the strip. Successive open corrugations or reverse folds are formed by the tooth of one gear cooperating with the hollow or space between the teeth of the opposing gear providing in effect successive transverse corrugations in the buffing material. It will be observed that while the corrugating gears are of equal diameter and of equal pitch the gear centers are spaced apart so that the outside diameter of one gear is tangent to the outside diameter of the other gear providing a space between the point of one gear and the hollow of its opposing gear into which the multi-ply thickness of the buffing material is compressed to produce successive substantially uniform corrugations transversely throughout substantially the full width of the material. In order to prevent the material from being jammed between the teeth and carried around with the gears, spaced upper and lower guide rods 72 are provided which extend between grooves 74 formed in the gears to a depth of the bottom diameter of the gear teeth as shown. Thus, the material is prevented from being jammed into the bottom of the space between the teeth and is stripped away from the gear teeth as it passes beyond the corrugating gears. It will be observed that the guide rods 72 are curved outwardly slightly immediately beyond the corrugating gears to permit clearance for the corrugated material to be gradually stripped away from the teeth as it leaves the corrugating gears. It will be understood that the folded edge of the material wrapped about the stationary tube 58 is free to slide along the tube and to be compressed longitudinally into puckered relation as the extended portions of the material are provided with substantially uniform transverse corrugations.

The guide rods 72 are then curved inwardly again to assume their normal spaced relation to control the width of the element and to guide the material with its open folds or corrugations between a series of upper and lower driven retarding gears 76, 77, respectively, which are arranged to be driven at a slower rate of speed than the corrugating gears and operate to hold the material back so that the open corrugations are gradually compressed together and compacted into closely spaced relation as shown in FIG. 12.

The drive for the gears indicated in FIGS. 11 and 12 may be taken from a vertical drive shaft 78 which may be rotated from any usual source of power, such as an electric motor, not shown. The drive shaft 78 may be connected by bevel gears 80 to a horizontal shaft 82 having a spur gear 84 which meshes with a gear 86 on shaft 88. Gear 86 is in mesh with a gear 89 fast on the upper corrugating gear shaft 90 to drive the upper corrugating gear 68 in a clockwise direction. The gear 86 also meshes with a gear 92 on a shaft 94 which in turn meshes with a gear 96 fast on a lower corrugating gear shaft 98 for driving the lower corrugating gear 70 in a counterclockwise direction.

The upper and lower series of retarding gears 76, 77 are driven from their respective corrugating gear shafts 90, 98 as shown. The upper corrugating gear shaft 90 is provided with a pinion 100 which is operatively connected by an idler gear 102 to the first one of the series of upper retarding gears 76 to rotate the same in a clockwise direction at a slower rate of linear speed than the linear speed of the corrugating gear, and the second and third upper retarding gears 76 are connected to the first gear by idler gears 104 to effect rotation of the gears 76 in a clockwise direction. The lower series of retarding gears 77 are similarly driven in a counterclockwise direction through pinion 106, idler 108, first retarding gear 77 and idler gears connecting the first gear 77 to the second and third gears in the series. It will be observed that the rods 72 also extend through grooves 73 formed in the retarding gears 76, 77 and serve to guide and maintain the corrugations at a uniform width as the corrugated strip is compressed and advanced therebetween. The rods 72 may be connected at one end to frame members 75, the other ends being curved around the endmost upper and lower retarding gears 76, 77, respectively, as shown.

From the description thus far, it will be seen that in operation the multi-ply or laminated cloth strip folded upon itself is provided with open corrugations by the corrugating gears 68 and 70, and as the corrugated material is advanced through the retarding gears 76, 77, the teeth thereof project into the edges of the corrugations to retard the linear speed of the strip relative to the speed at which the strip passes through the corrugating gears so that in operation the open corrugations are gradually closed to longitudinally contract and compress the corrugations together as shown in FIG. 2. It will be understood that as the corrugations are longitudinally compressed by the retarding action of the gears "76, 77, the folded edge of the material wrapped about the stationary tube 58 may be further longitudinally compressed and puckered. The strip may preferably be longitudinally contracted an amount equal to from one-half to onefourth of its normal uncorrugated length, and in this manner the density of the buifing face of the buff may be varied to form a harder or softer buif whenever desired. In practice a one-third contraction of the strip provides a buffing face of a density commonly utilized in the bufling industry. However, in some cases the strip may be contracted to more than one-fourth of its uncorrugated 1ength corrugations in the strip extend uniformly from a point spaced outwardly from the folded edge of the strip to the opposite marginal edge, and the folded edge assumes a gathered or puckered condition. It will also be observed that provision is made for retaining the corrugations in their longitudinally compressed condition by means cooperating with the inner portion of the strip along a line spaced outwardly from the folded edge, either by stitching extended through the corrugations, or by the other means heretofore described. In a modified embodiment of the invention the material may comprise a multiply strip of unfolded cloth or other bufiing material which may be provided with transverse corrugations, as above defined, and which extend throughout the full width thereof.

It will also be observed that the present method and apparatus provide an efficient, economical method of making a novel and improved buifing element for use in making a buffing wheel or buffing roll.

The present method provides a buffing element particularly adapted for use in the manufacture of a buffing roll or section wherein the transverse corrugations are uniform and, consequently, pick up the bufiing compound uniformly to enable the work to be buffed in a highly efficient manner. In practice the number of plies of cloth or other buffing material may be varied to provide buffing surfaces of different densities and the spacing between the convolutions or of the individual sections varied to provide a hard or soft buffing surface.

In practice it is preferred to extend a Wire 14 within the folded edge of the U-shaped bufiing material to atford better control of the lengthwise movement or advance of the material to hold the material down and to prevent lateral outward displacement thereof. The wire 14 is also of particular advantage for use when the U-shaped corrugated material is helically wound directly onto a tubular core member between the convolutions of a clamping spring wherein the free end of the wire may be first secured to the core member. However, in its broader aspects the present invention contemplates production of the corrugated buffing element either in its U-shaped form or in its unfolded condition without the use of a wire, particularly in the embodiment of the invention wherein the corrugations are stitched to retain them in their contracted and compressed condition. When the U-shaped material is produced without a wire, the folded edge of the material passes over the stationary rod 58 to hold the material down during the corrugating operation.

In some instances it may be preferred to dampen the buffing material prior to corrugating the same so that when the subsequently corrugated strip is dried the corrugations will be more firmly set and relatively rigid, particularly when the material is initially provided with a starch or like filler.

It will be understood that wherever the term buffing element or material is used herein, it is intended to mean a surface treating material capable of polishing, buffing and/ or abrading, and whenever the term buffing wheel is used it is intended to mean a single section or a buffing roll.

While the preferred embodiment of the invention has been herein illustrated and described, it will be understood that the invention may be embodied in other forms within the scope of the following claims.

Having thus described the invention, what is claimed is:

1. The method of making a buffing wheel element comprising the steps of: folding an elongated continuous strip of sheet buffing material into a U-shape in cross section; moving said U-shaped strip lengthwise; corrugating the leg portions of said U-shaped strip while in motion to provide uniform corrugation folds therein; longitudinally contracting the corrugated portion of said strip, and securing said leg portions together adjacent the fold thereof.

2. The method of making a buffing wheel element comprising the steps of: moving an elongated continuous strip of sheet buffing material lengthwise; corrugating the strip while in motion to provide longitudinally uniform folds therein; and longitudinally contracting the corrugated portion of said strip while the entire corrugated portion of said strip is in motion, and securing said leg portions together adjacent the bottom edge thereof.

3. The method of making a buffing wheel element comprising the steps of: folding an elongated continuous web of sheet buffing material upon itself to provide a strip U-shaped in cross section; moving said U-shaped strip lengthwise; transversely corrugating the leg portions of said U-shaped strip while in motion to provide folds therein; and longitudinally contracting the corrugated portion of said strip while the entire corrugated portion of said strip is in motion, the corrugating step providing corrugations extending from a point spaced outwardly from the fold of the U to the opposite marginal edge of the strip and securing the leg portions together adjacent the fold thereof.

4. The method of making a buffing wheel element comprising the steps of: moving an elongated continuous strip of sheet buffing material lengthwise; corrugating the strip while in motion to provide substantially uniform folds therein; and longitudinally contracting the corrugated portion of said strip while the entire corrugated portion of said strip is in motion, the corrugations extending the full width of the strip, and securing said leg portions together adjacent the fold thereof.

5. The method of making a buffing wheel element comprising the steps of: folding an elongated continuous web of sheet buffing material upon itself to provide a strip U-shaped in cross section; moving said U-shaped strip lengthwise; corrugating the leg portions of said U-shaped strip while in motion to provide uniform folds therein; and longitudinally contracting the corrugated portion of said strip into substantially one third of its uncorrugated state, and securing said leg portions together adjacent the fold thereof.

6. The method of making a'buffing wheel element comprising the steps of: folding an elongated continuous web of sheet bulfing material upon itself to provide a strip U-shaped in cross section; moving said U-shaped strip lengthwise; corrugating the leg portions of said U-shaped strip while in motion to provide uniform corrugations therein; longitudinally contracting the corrugated portion of said strip; and then securing the corrugations in their contracted state during the continued movement of the strip along a line parallel to and spaced outwardly from the fold of the U.

7. The method of making a buffing wheel element comprising the steps of: moving an elongated continuous strip of sheet buffing material lengthwise; transversely corrugating the strip while in motion to provide uniform corrugations therein; and longitudinally contracting the corrugated portion of said strip to provide a buffing surface having uniform corrugations therein while the entire corrugated portion of the strip is in motion, and securing said corrugations together adjacent their bottom edges.

8. The method of making a buffing wheel element comprising the steps of: longitudinally advancing an elongated continuous U-shaped multi-ply strip of buffing material; guiding the strip along a stationary element engaged within the U of the strip; transversely corrugating the leg portions of said strip while being guided to provide uniform reverse folds therein; retarding the linear speed of the corrugated portion of the strip to effect longitudinal contraction and compression of the folds; and then securing the corrugations in their contracted state during the continued movement of the strip along a line adjacent the fold of the U.

9. The method defined in claim 8 wherein the step The number of corrugations per linear inch of the strip is dependent upon the relative speed of the corrugating gears with respect to the retarding gears, and in this manner the density of the bufling face may be varied. The density may also be varied by varying the number of plies of bulfing material used in forming the strip. While in some instances single or multi-ply strips having a few plies may be utilized, the strip may preferably comprise from eight to eighteen plies of the buffing material.

In the illustrated embodiment of the invention at least one of the brackets carrying the retarding gears, herein shown as the lower bracket 112, may be pivotally mounted at 114 and spring ressed upwardly to urge the projecting teeth of the retarding gears into operative engagement with the edges of the corrugations. Thus, in the event that a relatively thicker portion of folded material, such as a spliced portion thereof, is passed between the gears, or in the event a rigid member is inadvertently passed between the rearding gears, the bracket may yield to prevent damage to the gears. As herein shown, a stud 116 extended through a clearance opening in a frame member 118 is threadedly secured to the underside of the bracket 112, and a spring 120 coiled about the stud 116 is interposed between the frame member and the bracket as shown. In the illustrated embodiment of the invention the corrugating gears 68, 70 extend transversely of the direction of movement of the material from a point spaced outwardly from the folded edge a short distance beyond the wire 14 and the stationary tube 58 as shown.

In the embodiment of the invention shown in FIG. 12 provision is made for securing the corrugations in their contracted condition by stitching indicated at 121, and as herein diagrammatically indicated, a stitching head 122 is arranged to apply the stitching through and around the corrugations to retain them in their compacted condition. It will be observed that when the closely compacted corrugated strip passes beyond the retarding gears the folded edge slides off the stationary tube 58 and is again engaged with the wire 14. In order to maintain the corrugations in their closely compacted condition during the stitching operation, a pair of auxiliary retarding gears 124, 125 is disposed beyond the stitching head and may be driven from the endmost pair of the series of retarding gears 76, 77 by chain and sprocket drives 126, 127, respectively. The elongated strip of corrugated buifiing material thus prepared may be rolled up and stored for future use in making bufling wheels of the type shown in FIGS. 5 and 7. It will be seen that the stitching is applied along a line spaced from the lower or folded edge and above the wire 14, the extended portions of the corrugations being free to open or expand uniformly when the strip is subsequently formed into a ring or spirally wound upon a core member to produce the bufiing wheel or roll.

In the above-described embodiment of the invention the buffing element is produced from a web of laminated or multi-ply cloth which may be stitched together along a medial line as shown in FIG. 9. However, the stitching 40 may be omitted if desired. In a modified embodiment of the invention, as shown in FIGS. 17 and 18, the material may comprise two multi-ply webs of cloth 130, 132 connected in spaced relation to one or more outer webs 134 by stitching 135, the material being folded inwardly upon itself, as shown in FIG. 18, and provided with corrugations in the manner above described. FIG. 19 illusstrates a further modification wherein a relatively narrower unfolded web of multi-ply bufiing material 136 may be provided with corrugations in the manner above described. FIG. illustrates a folded and corrugated strip 138 which is provided with an inner cardboard filler 140 for producing a strip of slightly greater thickness than the normal thickness thereof. FIG. 21 illustrates a strip of abrasive material 142 commonly referred to as grit cloth which comprises a loosely woven fabric material treated by impregnating it with silicon carbide or aluminum oxide and which has been corrugated in accordance 6 with'the present invention and provided with inner and outer shield elements 143 and 144; and FIG. 21a illustrates a corrugated strip 145 of abrasive material similar to that illustrated in FIG. 21 in which the shield elements 143 and 144 have been omitted.

The apparatus shown in FIGS. 8 to 16 contemplates the retention of the corrugations in their longitudinally compressed and closely compacted condition by stitching passing through the material and in a direction perpendicular to the direction of the corrugations. However, the present invention also contemplates other preferred means for retaining the corrugations in their closely compacted condition, one such means being illustrated in FIG. 22 wherein the corrugated strip 144, produced in the manner shown in FIGS. 11 and 12, but without the stitching 121, may be wound directly onto a hollow core member 36 between the convolutions of a clamping spring 38 (see FIG. 23) to produce a bulfing roll of the type shown in FIG. 7. In practice the free end of the wire 14 may be secured to the hollow core member 36, and the latter may be rotated in timed relation to the advance of the material being produced by the corrugating mechanism. When the roll is completely wound the strip may be severed, and thereafter the spring 38 may be compressed to grip and retain the corrugated material therebetween, preferably by recessed end collars 150, 152 in the manner illustrated in FIG. 7. In use the completed bufiing roll thus assembled is adapted to be mounted on an arbor 154 and secured thereto by a nut 156.

, Another preferred expedient contemplated by the present invention for retaining the corrugations in their uniformly compacted condition is illustrated in FIG. 24 wherein the strip of corrugated material produced by the apparatus shown in FIG. 12, but without stitching, may be stapled directly to a helically shaped springlike metal band. In operation the folded edge of the corrugated material may be guided into superimposed relation to the metal band around a curved guide member 160, and the superimposed strip and band may be rotated and advanced by suitable serrated feed rollers, one of which is shown at 162, to intermittently advance the material past a stapling head indicated generally at 164.

As herein illustrated, the staples may be set at an angle to permit close spacing of the staples when desired and are preferably applied thorugh the corrugations at a point beyond the wire 14. The helical stapled strip thus produced may be secured to a tubular core member to provide a bufiing roll, or a section of the helical material may be cut off to provide a ring for producing a single section bufling wheel. In some instances it may be desirable to provide a plurality of rows of staples to secure the corrugated strip to the helical metal band, and the rows may be set substantially parallel to the wire 14.

A preferred form of helical metal band to which the present corrugated bufling element may be stapled is L-shaped in cross section, as indicated at 166 in FIG. 25, and having an outwardly extended leg or flange 168. The strip may be secured to a tubular core member at the flange portion.

When single section buffing wheels are to be formed from a length of the buffing material stapled to a metal band, the helically formed metal bands may take the form shown in cross section in either FIGS. 26 or 27, FIG. 26 showing an inwardly bent flange 170 to add rigidity to the band, and FIG. 27 showing a flat band 172. The structure and method of fastening the corrugated strip to the helical metal band forms a portion of the subject matter of and is claimed in my copending application, Serial No. 814,750, filed May 21, 1959.

From the above description it will be seen that the present novel and improved method and apparatus produces a corrugated buifing element wherein uniform and closely compacted transversely extended corrugations are provided in preferably a multi-ply web of cloth or other known surface treating material folded upon itself. The

of securing the corrugations in their contracted state comprises a stitching operation.

10. The method of making a buffing wheel element comprising the steps of: longitudinally advancing an elongated continuous U-shaped multi-ply strip of bufiing material; positioning a wire within the U of the strip to be advanced therewith; guiding the strip along a stationary tube engaged within the U of the strip and through which the wire is advanced; corrugating the leg portions of the strip while being thus guided to provide uniform reverse folds therein; retarding the linear speed of the corrugated portion of the strip to effect longitudinal contraction of the folds; longitudinally compressing the folded edge of the material during the corrugating and contracting operations to form puckers therein; and then securing the corrugations in their contracted condition along a line adjacent the fold of the U during the continued movement of the strip after it leaves the stationary tube and while supported by said wire.

11. The method defined by claim 10 wherein the step of securing the corrugations in their contracted state comprises clamping the strip between the convolutions of a spring mounted on a core member.

12. The method of making a buifing Wheel element which comprises the steps of: moving a continuous strip of sheet buffing material lengthwise; corrugating the strip while in motion to provide longitudinally uniform folds therein; and retaining a section of the corrugations under longitudinal compression while applying force to compact a number of the corrugations while the entire corrugated portion of the strip is in motion.

13. The method of making a buffing wheel element which comprises the steps of: moving a continuous strip of sheet buffing material lengthwise; corrugating the strip while in motion to provide longitudinally uniform folds therein; retaining a section of the corrugations under longitudinal compression while applying force to compact a number of the corrugations While the entire corrugated portion of the strip is in motion; and progressively securing the compacted corrugations together adjacent the folded edge of the corrugations while the same are advancing.

14. The method of making a bufling wheel element as defined in claim 13 wherein the corrugations are secured together by stitching.

15. The method of making a buffing wheel element which comprises the steps of: continuously advancing a continuous strip of sheet buffing material; corrugating the strip while it is being advanced; retarding without stopping the advancing movement of the corrugated strip at a region spaced from that at which the corrugations are formed and applying compacting force to the corrugations at a point in advance of the region of retardation and securing the compacted corrugations together.

16. The method of making a buffing wheel element which comprises: continuously advancing a continuous strip of sheet buffing material at a given linear speed, corrugating the strip while it is being advanced at the given linear speed, and reducing the linear speed of the corrugations to less than the aforesaid linear speed to efiect compacting of the corrugations while the strip is in motion, and securing the compacted corrugations together.

References Cited by the Examiner UNITED STATES PATENTS 2,109,905 3/38 Lippitt 51-193 2,309,951 2/43 Hall 51-193 2,311,541 2/43 Hathaway 112-2 2,364,839 12/44 Young 1122 2,556,044 6/51 Sandman et al 51-193 2,693,064 11/54 Lyon 51193 2,698,783 1/55 Jones 51293 2,704,916 3/55 Peterson 51193 2,711,916 6/55 Davies 51--193 2,816,403 12/57 Peterson 51193 2,882,139 4/59 Rock 51293 2,938,567 5/60 Allan 154-33.05 XR ALEXANDER H. BRODMERKEL, Primary Examiner.

THOMAS J. HICKEY, MORRIS LIEBMAN,

Examiners, 

3. THE METHOD OF MAKING A BUFFING WHEEL ELEMENT COMPRISING THE STEPS OF: FOLDING AN ELONGATED CONTINUOUS WEB OF SHEET BUFFING MATERIAL UPON ITSELF TO PROVIDE A STRIP U-SHAPED IN CROSS SECTION; MOVING SAID U-SHAPED STRIP LENGTHWISE; TRANSVERSELY CORRUGATING THE LEG PORTIONS OF SAID U-SHAPED STRIP WHILE IN MOTION TO PROVIDE FOLDS THEREIN; AND LONGITUDINALLY CONTRACTING THE CORRUGATED PORTION OF SAID STRIP WHILE THE ENTIRE CORRUGATED PORTION OF SAID STRIP IS IN MOTION, THE CORRUGATING STEP PROVIDING CORRUGATIONS EXTENDING FROM A POINT SPACE OUTWARDLY FROM THE FOLD OF THE U TO THE OPPOSITE MARGINAL EDGE OF THE STRIP AND SECURING THE LEG PORTIONS TOGETHER ADJACENT THE FOLD THEREOF. 